Earth mover frame stabilizer



1964 H. w. ROCKWELL EI'AL 3,

EARTH MOVER FRAME STABILIZER 2 Sheets-Sheet 1 Filed June 27, 1961 J 1964 H. w. ROCKWELL ETAL 3,113,238

EARTH MOVER FRAME STABILIZER Filed June 27, 1961 2 Sheets-Sheet 2 United States Patent 3,118,238 EARTH MGVER FRAME STABILIZER Harvey W. Rockwell, (Seder Rapids, and Dale W. Hawk,

Marion, Iowa, assignors to Allis-Chalmers Manufacturing Company, Milwaukee, Wis.

Filed June 27, 196i, Ser. No. 119,891 7 Claims. (Cl. 37129) This invention relates to a stabilizer for the frame of an earth mover and is more particularly concerned with stabilizing the draft yoke and scraper bowl sections of a scraper.

i-leretofore it has been a common practice in earth mover design to provide a bowl section with wh els at its rear end and a draft frame or yoke section having a pair of rearwardly extending legs which pivot to the sides of the scraper bowl. A substantial portion of the bowl extends forwardly from the transverse pivots between the legs of the yoke and the bowl sides, and it is an object of this invention to transversely stabilize the forward end of the bowl section relative to the draft yoke.

It is a further object of this invention to provide stabilizing means for limiting relative lateral movement between the yoke and bowl sections which does not interfere with the operators observation of the loading and unloading operations of the earth mover.

Heretofore a hydraulic ram has been mounted in an upstanding position for operating an apron pivotally mounted at the front end of the scraper bowl and such hydraulic ram has heretofore been positioned centrally at the junction of the legs of the draft yoke section. A reduction of overall cost and a saving in space is achieved by this invention through use of the mounting structure for the apron lift rain as a part of the stabilizer means.

Therefore, it is an object of this invention to provide a stabilizing mechanism for yoke and bowl sections of an earth mover which uses the mounting structure for the apron lift ram as one of the two guide structures thereof.

These and other objects of this invention will be apparent to those familiar with the art to which this invention relates, when the following description is read in conjunction with the drawings in which:

FIG. 1 is a side view of an earth mover in which this invention is incorporated;

FiG. 2 is a section taken along the line ll-II in FIG. 1 with the bowl in its lowest excavating position;

FiG. 3 is a section taken along the line Illlil in FIG. 2;

ES. 4 is a top View of a portion of the scra er shown in PEG. 1; and

FIG. 5 is a section taken alon the line VV in FIG. 4.

Referring to FIGS. 1 and 4, a two engine earth mover 11 has a draft yoke section 12 which is pivotally connected in a conventional manner to a two wheel tractor 13 for steering movement about a vertical pivot axis. The yoke section 12 incnides a pair of legs 34, 15 which extend rearwardly to pivotally connect on the sides l5, 17 of the bowl section 18 on a transverse pivot axis 19. The bowl section 18 is supported at its rear end by a pair of wheels 21, only one of which is shown, and an engine 22 is provided on the rear end of bowl section 18 to dr 'e the wheels 21.

Referring also to FIGS. 2 and 3, the forward ends of the sides l6, 17 are interconnected by a transverse brace 23. This transverse brace 23 a guide structure 24 welded thereto at the central portion thereof. A cooperating guide structure 26 is formed on the yoke 12 at the junction of legs 14, 15. As shown in FIGS. 4 and 5, the guide structure is the well structure in which the lift ram 27 for apron Si is mounted. The lower Patented Jan. 21, tees "ice end of the apron lift ram 27 is pivotally connected to a bracket 28 rigidly secured to laterally opposite sidewalls 29, 31 of the well structure. The well structure is also provided with a front wall 32 and a rear wall 33. The well structure is open at its upper end to permit the top portion of thte apron lift ram 27 to extend therefrom for pivotal connection to an apron lift lever The front end of the apron lift lever is pivotally connected to the yoke by a pivot pin 36 and the rear end of the apron lift lever 34 carries a sheave 37 over which the apron lift cable 33 is reaved for connection at one end of the apron 3i and at its other end to the well structure 26 by a transverse pin 41.

The laterally outer surfaces 53, 54 of the sidewalls 29, 31 of the well structure serve as guide surfaces or tracks for a pair of rollers 42, 43 included in guide structure 24. The rollers 42, 43 are pivotally connected to forwardly extending ears 44, 46 of the guide structure 2 The guide structure 24 also includes a pair of bracing struts 47, 48. As the bowl section is raised and lowered by the bow lift rams 51, 52, which are pivotally connected at their opposite ends to the yoke section 12 and bowl section 18, the rollers follow an arcuate path on the thrust transmitting guide suriaces 53, 54 on the sidewalls 29, 31 respectively. Since the surfaces 53, 54 lie in parallel vertical planes which have a right angle relationship to the axis 19, the rollers and surfaces 53, 54- will maintain transverse thrust transmitting relation therebetween throughout the angle of relative rotation of the yoke and bowl sections.

The brace 23 is positioned on the scraper bowl above the cutting edge 61 so as not to interfere with loading operations. The legs l4, 15 of the yoke are pivotally connected to the sides of the scraper by a pair of ball and socket joints 62, 63. By providing the stabilizing arrangement between the forward end of the bowl section and the draft yoke, the width of the legs and the size of the pivot connections between the legs of the draft frame and the bowl section can be reduced in size. This permits a higher percentage of the overall scraper width to be used for the interior bowl width thereby increasing pay load. By locating the stabilizing structures as illustrated, that is, in close proximity to the central longitudinal plane of the earth mover, the operators vision of the scraper loading operations is not impaired as it might otherwise be. Also the well structure for the apron lift ram is caused to serve a double function by virtue of using the laterally outer surfaces thereof as tracks for the rollers 32, 43 of guide structure 24.

The centrally positioned stabilizing mechanism of this invention permits use of minimum clearance between the guide structures of the stabilizing mechanism thus providing excellent stabilization against relative lateral movement between the yoke and bowl. in making a sharp turn with a tractor scraper of the type having a yoke and a bowl interconnected on a transverse axis, the yoke will twist about an imaginary longitudinal axis, approximately at right angles to the transverse pivot axis and extending longitudinally through the forward portion of the yoke. The twisting of yoke occurs particularly at the end of a cut when the operator turns sharply from the cut with a full At this time the bowl is raised from its excavating position to a carry position in which the rollers 42, 43 are at approximately the same height as the longitudinal axis of twist. Thus the forward part of one leg of the yoke will be raised and the forward part of the other leg of the yoke will be lowered. Such deflection required considerable lateral clearance to he provided between the guide members of prior art stabilizing arrangements, wherein guide rollers were placed on the legs of the yoke to bear against the forward part of the side frame of the scraper bowl. The greater the lateral clearance allowed between the stabilizing members, the less effective the stabilizing means is in providing the desired lateral stability. In the present invention the guide structures of the stabiling means are located adjacent the rear of the junction of the legs of the yoke in close proximity to the central longitudinal plane of earth rnover. Thus the clearance allowance required for twisting of the yolze in sharp turns is minimized and the relatively close it permitted between the guide structure provides excellent lateral stabilization.

Although a single embodiment of this invention has been illustrated and described, it is not intended to limit this invention except as necessitated by the scope of the appended claims.

What is claimed is:

1. In an earth mover of the type having a bowl section with a front apron and a draft yoke section which includes a pair of legs extending rearwardly and connectpivotally to opposite sides of the bowl section on a transverse axis, combination compris ng: a well structure formed on said yoke section at the junction of said legs and having m open upper end, a hydraulic rarn disposed at least in part within said well structure having one end extending through said open upper end and having its other end connec ed to said well structure, means connecting said apron and said one end or" said hydraulic rain, a transversely extending brace interconnecting the forward ends of said sides of said bowl section, a guide structure mounted on said brace intermediate its opposite ends, and a vertical guide surface formed on one of said structures in transverse thrust transmitting relation to the other of said structures.

2. The apparatus set forth in claim 1 wherein said other of said structures includes a roller having transverse contact with said surface.

3. The apparatus set forth in claim 1 and further comprising a second vertical guide surface formed on said one of said structures in parallel transversely spaced relation to the other vertical guide surface and in transverse thrust transmitting relation to said other of said structures.

4. The apparatus set forth in claim 3 wherein said other of said structures includes a roller.

5. in an earth mover of the type having a bowl section with a front apron and a draft yoke section which includes a pair of legs extending rearwardly and connecting pivotally to opposite sides of the bowl section on a transverse axis, the combination comprising: a well structur formed on said yoke section at the junction of said legs and having an open upper end, a hydraulic ram disposed at least in part within said well structure having one end extending through said open upper end and having its oth 1' end connected to said well structure, means connecting said apron and said one end of said hydraulic mm, a transversely extending brace structure on the forward end of said bowl section, a pair of vertical guide surfaces formed on one of said structures in transversely spaced parallel relation to one another and a pair of guide rollers rotatably mounted on the other of said structures in transverse thrust transmitting relation to said guide surfaces, respectively.

6. The apparatus set forth in claim 5 wherein said guide surfaces are formed on laterally opposite sides or" said Well structure. a

7. In an earth rnover of the type having a bowl elemerit, a front apron element, and a draft yoke which includes a pair of legs extending rearwardly and connecthig pivotally to opposite sides of the bowl element on a transverse axis, the cornbh tion comprising: a well structure formed on said yoke at the junction of said legs and having an open upper end, a hydraulic ram disposed at least in part within said well structure having one end extending through said open upper end and having its other end connected to said well structure, means connecting said one end of said hydraulic ram and one of said elements, a transversely extending brace interconnecting the forward ends of said sides of said bowl element, a guide structure mounted on said brace intermediate its opposite ends, and a vertical guide surface formed on one of said structures in transverse thrust transmitting relation to the other of said structures.

References Cited in the file of this patent UNITED STATES PATENTS 2,203,713 Austin June 11, 1940 2,312,311 Armington et al. Mar. 2, 1943 2,318,190 Eerner May 4, 1943 2,581,073 Brewer Jan. 1, 1952 

7. IN AN EARTH MOVER OF THE TYPE HAVING A BOWL ELEMENT, A FRONT APRON ELEMENT, AND A DRAFT YOKE WHICH INCLUDES A PAIR OF LEGS EXTENDING REARWARDLY AND CONNECTING PIVOTALLY TO OPPOSITE SIDES OF THE BOWL ELEMENT ON A TRANSVERSE AXIS, THE COMBINATION COMPRISING: A WELL STRUCTURE FORMED ON SAID YOKE AT THE JUNCTION OF SAID LEGS AND HAVING AN OPEN UPPER END, A HYDRAULIC RAM DISPOSED AT LEAST IN PART WITHIN SAID WELL STRUCTURE HAVING ONE END EXTENDING THROUGH SAID OPEN UPPER END AND HAVING ITS OTHER END CONNECTED TO SAID WELL STRUCTURE, MEANS CONNECTING SAID ONE END OF SAID HYDRAULIC RAM AND ONE OF SAID ELEMENTS, A TRANSVERSELY EXTENDING BRACE INTERCONNECTING THE FORWARD ENDS OF SAID SIDES OF SAID BOWL ELEMENT, A GUIDE STRUCTURE MOUNTED ON SAID BRACE INTERMEDIATE ITS OPPOSITE ENDS, AND A VERTICAL GUIDE SURFACE FORMED ON ONE OF SAID STRUCTURES IN TRANSVERSE THRUST TRANSMITTING RELATION TO THE OTHER OF SAID STRUCTURES. 